In response to Reconstruction, people who believed the white race is superior to people of other races formed groups.

White Supremacy.

Explanation:

The American Civil War was also referred to as War between the States and it was fought from the 12th of April, 1861 to the 9th of April, 1865. The war was simply between the Southern states that seceded to form Confederate States and the Northern states that were still loyal to the Union.

After the American Civil War, the turbulent era in which efforts were made by the government of the United States of America to reintegrate the Southern states from the Confederacy was known as the Reconstruction era. It began on the 8th of December, 1863 to 31st of March, 1877.

In response to Reconstruction, those who believed that the white race was superior to people of other races such as Black Americans, Asians, American Indians, Hispanics, etc., formed the White Supremacy groups.

These group of Americans held strongly unto the believe that all white (light-skinned) people living in the United States of America are naturally superior to the people of other races and as such should dominate them.

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